1. Field of Invention
The present invention relates to an access device, such as a ladder, which provides access between a substrate surface and an elevated surface. The present invention, in particular, relates to an access device which is particularly suitable for attachment to a locomotive, or other vehicle, where access may be required between a platform and a vehicle, and also between a lower substrate surface and the vehicle, and, whereby the access device is wholly retained such as not to protrude from the vehicle whilst the vehicle is in use.
2. Description of Prior Art
The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement or any form of suggestion that that prior art forms part of the common general knowledge.
A variety of different access devices are presently known, to provide access between upper and lower surfaces. Various such devices are disclosed in granted and pending patent applications made by the Applicants, such as in the Applicants' earlier Australian patent application Nos. 67555/94 and 14992/97, and corresponding overseas applications.
For example, in the Applicants' earlier patent application No. 67555/94, the access device provides access between a substrate surface and an elevated surface of a vehicle, whereby the device is provided with a pair of rigid arms on each side of the access device, such that the device is pivotally movable from a stable lower position to a stable upper position. In the lower position, the access device is inclined at between 60° and 75° relative to a substantially horizontal substrate surface, with the upper end of the device in a position substantially adjacent to and forwardly of the elevated surface. In the upper position, that access device is provided substantially vertically or at a rearwardly inclined angle in a position which is totally upward and rearward of the elevated surface.
Also, in the Applicants' earlier patent application No. 14992/97, there is provided an access device which, instead of being stored upwardly and rearward of the elevated surface, the device is stored in a substantially horizontal position on the side or across the front of the vehicle. This is achieved by moving the device from the boarding to the storage position wherein, firstly, the device is rotated about a first axis, and secondly, the device is retracted such that the second end of the device is retracted towards the elevated surface.
While the Applicants' earlier access device embodiments provide significant advantages over the prior art devices, it will be appreciated that each of these devices is particularly designed to complement quite unique vehicles, wherein the functional uses of the particular vehicle limits the options for storage of the access device and, the different physical embodiments of the vehicles necessitate different designs of access devices for access between different surfaces.